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Topic: Windscreen Wipers On Aircraft
Username: readytotaxi
Posted 2012-12-20 09:27:18 and read 8263 times.

Given the extreme temps that they can go through I was wondering how often they get changed, do they last out a year?
Are they made of the same compound are car wipers?
Cheers!

Topic: RE: Windscreen Wipers On Aircraft
Username: b78710
Posted 2012-12-20 09:43:56 and read 8253 times.

Very rarely changed. In the 10 years I've now been working aircraft (mixture of ramp and hangar work) The only windscreen wipers I have removed have been to facilitate windscreen removals.

Maybe I've just been lucky

Topic: RE: Windscreen Wipers On Aircraft
Username: m1m2
Posted 2012-12-20 09:50:15 and read 8245 times.

Same here, and I work on aircraft that fly several cycles a day. I don't think they get used that much, probably just occasionally during taxi and sometimes when landing. Not sure about the take off roll, maybe some of our pilot friends here can help us with that.

Topic: RE: Windscreen Wipers On Aircraft
Username: yeelep
Posted 2012-12-20 11:04:13 and read 8189 times.

Up until a couple of years ago we rarely changed them. Now they are changed every year as part of a winter prep task card. I also will replace one when changing a window due to scratches on the outer pane.

Topic: RE: Windscreen Wipers On Aircraft
Username: A320ajm
Posted 2012-12-20 12:28:57 and read 8131 times.

Not to hijack this post but....
When I was young, 14 or 15 perhaps, I asked my flying instructor (who now works for a UK low-cost airline) if commercial aircraft had wipers. He looked at me and laughed like it was a stupid question, and said he didn't think so. This post just reminded me of this time   And probably now is the first time I've ever thought about them having windscreen wipers!

A320ajm

Topic: RE: Windscreen Wipers On Aircraft
Username: CCA
Posted 2012-12-20 13:03:02 and read 8107 times.

When ever its raining and you can't see the taxiways or runway well enough they get used, it depends on the severity of the rain and the speed of the aircraft, as you can imagine light rain at high speed is similar to heavier rain at slow speed.

The windscreens are also treated with a hydrophobic coating which repels water, I've asked for reapplication of the coating more times that I've written wipers up in the tech log. Most times the wiper just fails but its rare, 747 wipers seem to be very good.

Topic: RE: Windscreen Wipers On Aircraft
Username: fr8mech
Posted 2012-12-20 13:52:32 and read 8060 times.

Quoting b78710 (Reply 1):
Maybe I've just been lucky

Yeah, you've been lucky.

With my operator, wipers are changed on condition. I'm sure we have an inspection program for them. But, I'm sure it's a heavy maintenance task card.

Topic: RE: Windscreen Wipers On Aircraft
Username: b78710
Posted 2012-12-20 17:34:33 and read 7950 times.

We don't have an inspection for them as far as I'm aware.

If the crew snag it, it would get changed. I've never seen one snagged

Topic: RE: Windscreen Wipers On Aircraft
Username: HAWK21M
Posted 2012-12-21 01:03:47 and read 7808 times.

Quoting b78710 (Reply 7):

If the crew snag it, it would get changed. I've never seen one snagged

Normally its the Inadequately wiping snag which is Normally rectified by Varying the Wiper blade tension.

Topic: RE: Windscreen Wipers On Aircraft
Username: Max Q
Posted 2012-12-21 01:18:11 and read 7804 times.

I wish the wipers on my Toyota were as good !


Funny fact, never seen an airspeed limitation on wipers.


Not that you need them at 350 knots..

Topic: RE: Windscreen Wipers On Aircraft
Username: PGNCS
Posted 2012-12-21 01:52:38 and read 7792 times.

Quoting Max Q (Reply 9):
Funny fact, never seen an airspeed limitation on wipers.

Never say never...A-320 series max wiper speed: 230 Knots.

Of course we know all about your unnatural affection for Boeing products, so that explains that!  

Topic: RE: Windscreen Wipers On Aircraft
Username: TWA772LR
Posted 2012-12-21 10:42:47 and read 7605 times.

I imagine they are like car wipers, on steroids.

This is probably the dumbest question I will ask on this site, do airplanes have windshield wiper fluid, like cars?

Topic: RE: Windscreen Wipers On Aircraft
Username: yeelep
Posted 2012-12-21 10:49:44 and read 7598 times.

Quoting TWA772LR (Reply 11):

On the 737's the answer is no and kinda. up to the NG's they have a fluid system like a cars. But instead of a washer type fluid, a product called Rainboe (think industrial strength Rainex) is sprayed. The NG's have none.

Topic: RE: Windscreen Wipers On Aircraft
Username: musang
Posted 2012-12-21 10:55:45 and read 7594 times.

Very interesting replies from mechanics.

I drive 737s, short haul of course, and I would guess I snag one maybe three times a year, always because the contact edge (the approx 2mm wide strip) is ripping off the main blade body.

No rain repellant is used at all, engineering dept confirm this is company-wide, and thinks its also nationwide, because of the carcinogenic nature of the stuff. 146s had a "Rainboe" repellant spray system, but it was deactivated before I got to them.

No hard stats available but the technician I spoke to estimates they change one blade a month on a fleet of about 30.

No wiper speed limit on 737s but they are difficult to park (against the airflow) above about 180 knots. They aren't needed as soon as you leave the ground, so are routinely parked immediately. On a rainy approach, airspeed is low enough such that the airflow does not overpower them.

I saw cockpit pics in an article on 727s with a South American operator, which showed the blades parked in the vertical position rather than horizontal. Why would they decide to do this? Could anyone offer an opinion on why this isn't standard on all types (it is on some commuters). On 727/737 the first places ice builds up on the front screen is top of the centre pillar and the lower outer corners, so the outer end of the parked blade would be susceptible in either of the two park positions. Having said that though, in years of 737 ops I've never seen ice restricting the blade when I needed to operate
it.

Regards - musang

Topic: RE: Windscreen Wipers On Aircraft
Username: tdscanuck
Posted 2012-12-21 11:12:54 and read 7584 times.

Quoting TWA772LR (Reply 11):
This is probably the dumbest question I will ask on this site, do airplanes have windshield wiper fluid, like cars?

It will show up on airplanes that don't have openable flight deck windows (e.g. 747, 787) because otherwise you can't clean with windows without a lift. On the rest...open window, clean from inside.

Tom.

Topic: RE: Windscreen Wipers On Aircraft
Username: b78710
Posted 2012-12-21 12:53:49 and read 7541 times.

Quoting TWA772LR (Reply 11):

Our jumbos have windscreen wash, in a little bottle in a stowage behind the captains seat

Topic: RE: Windscreen Wipers On Aircraft
Username: Starlionblue
Posted 2012-12-21 13:31:27 and read 7527 times.

Quoting TWA772LR (Reply 11):
This is probably the dumbest question I will ask on this site, do airplanes have windshield wiper fluid, like cars?

Not quite the same but there are aircraft with alcohol sprayers. The DC-3 has it if memory serves. However this is more to combat ice than to clean.

Topic: RE: Windscreen Wipers On Aircraft
Username: Bellerophon
Posted 2012-12-21 15:03:12 and read 7490 times.

m1m2


...Not sure about the take off roll, maybe some of our pilot friends here can help us with that...

Just as a piece of trivia, in general, most on the Concorde fleet were reluctant to use windshield wipers on the take-off roll.

The reason?

When raising the visor, there was only a small amount of clearance between a correctly parked wiper blade and a moving visor at the best of times. If, when you turned the wipers off they did not park themselves perfectly, they could foul the visor as it came up and prevent it from being raised fully.

If the visor couldn't be raised fully, you couldn't go supersonic, so jettison fuel and return to base!

On balance, most never used them on take-off, other than during the heaviest rainfall.

Best Regards

Bellerophon

Topic: RE: Windscreen Wipers On Aircraft
Username: flight152
Posted 2012-12-21 17:04:00 and read 7444 times.

Quoting Max Q (Reply 9):
Funny fact, never seen an airspeed limitation on wipers.

170 knots on the E145.

Topic: RE: Windscreen Wipers On Aircraft
Username: CCA
Posted 2012-12-21 20:24:42 and read 7395 times.

The 787 has vertical wipers I'd say it was to reduce drag every bit counts these days.

Topic: RE: Windscreen Wipers On Aircraft
Username: dlednicer
Posted 2012-12-21 22:31:02 and read 7358 times.

Quoting musang (Reply 13):
I saw cockpit pics in an article on 727s with a South American operator, which showed the blades parked in the vertical position rather than horizontal.

DC-10s have blades that park in the horizontal position, while on the MD11, the blades park in the vertical position. On DC-10s rebuilt as MD10s, the blades also park in the vertical position. Its a minor drag reduction item.

DC-10, MD10

View Large View Medium
Click here for bigger photo!

Photo © Art Brett - Photovation Images
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Photo © Ralph Duenas - Jetwash Images



MD11

View Large View Medium
Click here for bigger photo!

Photo © Terence Li

Topic: RE: Windscreen Wipers On Aircraft
Username: musang
Posted 2012-12-22 02:58:27 and read 7284 times.

Quoting b78710 (Reply 15):
Our jumbos have windscreen wash, in a little bottle in a stowage behind the captains seat

And 146s / Avro RJs. Pushbutton on the overhead, we could usually hear the pump, which sounded like a car washer pump, and it took a good few seconds for the fluid to climb the 4 feet of tubing to the nozzle, i.e. the one way valve didn't work!

Regards - musang

Topic: RE: Windscreen Wipers On Aircraft
Username: barney captain
Posted 2012-12-22 10:59:40 and read 7175 times.

The classic 737 wipers are so loud, I often joked that when they were needed, you could either see or hear - not both.   Thankfully the NG 's are vastly improved and work beautifully.

Topic: RE: Windscreen Wipers On Aircraft
Username: m1m2
Posted 2012-12-22 19:50:07 and read 7060 times.

Bellerophon

Thanks. That is interesting. Wouldn't have thought about that on Concorde. I'd imagine on take-off airflow would blow most of the rain off the windscreens.

Topic: RE: Windscreen Wipers On Aircraft
Username: amccann
Posted 2012-12-23 00:11:21 and read 6997 times.

Quoting dlednicer (Reply 20):
DC-10s have blades that park in the horizontal position, while on the MD11, the blades park in the vertical position. On DC-10s rebuilt as MD10s, the blades also park in the vertical position. Its a minor drag reduction item.

I think early MD11s were delivered with blades that parked horizontally. I know the switch to vertically parked blades was a two fold effort to reduce cockpit noise and reduce drag as part of the performance improvement program for the MD11.

MD-11 Wiper Question (by Fghtngsiouxatc Apr 4 2009 in Tech Ops)

Topic: RE: Windscreen Wipers On Aircraft
Username: HAWK21M
Posted 2012-12-23 02:37:05 and read 7117 times.

Quoting barney captain (Reply 22):

The classic 737 wipers are so loud, I often joked that when they were needed, you could either see or hear - not both.   Thankfully the NG 's are vastly improved and work beautifully.

What was the mod between the two types.....

Topic: RE: Windscreen Wipers On Aircraft
Username: GlobalMoose
Posted 2012-12-25 02:13:26 and read 6862 times.

I don't know about the other jet drivers here on the thread, but I've always found windshield wipers to be the funnest part of equipment on the aircraft...

Something about how they flail about on the windshield trying to compete against the airflow and rain simultaneously, coupled with their 'attempt' to park themselves and the accompanying KA-THUNK when they eventually decide to stow!

I always chuckle a bit to myself whenever I have (get) to use the wipers  

Topic: RE: Windscreen Wipers On Aircraft
Username: JAGflyer
Posted 2012-12-25 08:41:23 and read 6868 times.

Quoting yeelep (Reply 12):
Rainboe

A few years ago I worked as a stores person and I started LOL when I saw a tube of this on the shelf. Oh the jokes I thought of! Haha



Regarding the wipers, I have seen several wiper assemblies in stock on the shelf and I remember at least once when mtce called for a new one. We sent the U/S one out for repair if I remember right. I also recall several wiper motors being replaced during my time in stores.

[Edited 2012-12-25 08:44:20]

[Edited 2012-12-25 08:44:58]

Topic: RE: Windscreen Wipers On Aircraft
Username: n901wa
Posted 2012-12-25 13:20:23 and read 6787 times.

amccann is right. When we first got the early MD-11s, the wipers parked horizontal. They had a Mod later to have them park Vertical. The MDC guys said it was for noise, and less drag, we cracked up and told them they should mount the wings Vertical then, The guy didn't get the joke   . I think it was around N806DE that they came with the wipers vertical.

Its funny, I was trying to think the last time I changed a Blade. I think I only changed 1 set on a MD-11, and 1 set on a 727 but I changed quite a few wiper motors. Those suck. L-1011 ones stick in my head as being the worst for some reason. I think they came out from behind the inst panel, and took 2 guy to replace. Of course in the rain, at the gate with 200 people watching you  

Topic: RE: Windscreen Wipers On Aircraft
Username: rwessel
Posted 2012-12-26 22:13:06 and read 6556 times.

Quoting yeelep (Reply 12):
On the 737's the answer is no and kinda. up to the NG's they have a fluid system like a cars. But instead of a washer type fluid, a product called Rainboe (think industrial strength Rainex) is sprayed. The NG's have none.

On the SR-71, they used just a spray of rain-repellant fluid, without wipers. I'm guessing the flight environment was not conducive to the survival or rubber windshield wiper blades. IIRC, the XB-70 used a similar system.

Topic: RE: Windscreen Wipers On Aircraft
Username: HAWK21M
Posted 2012-12-27 02:55:19 and read 6502 times.

Quoting n901wa (Reply 28):
Its funny, I was trying to think the last time I changed a Blade. I think I only changed 1 set on a MD-11, and 1 set on a 727 but I changed quite a few wiper motors.

Thats odd.....The replacement rate of the wipers should be higher than the motor....maybe you were lucky.

On the B757s, the MTBUR for the motors should be 40,000 flt hrs, but there have been reports of removals less than 4,000 flight hrs, mainly caused by overtensioned or undertensioned blades.

Topic: RE: Windscreen Wipers On Aircraft
Username: n901wa
Posted 2012-12-27 05:37:36 and read 6494 times.

I think I did get lucky.   I did work the Line, and Hangar at a out station, that had good weather most of the yaer, so that would help.

Topic: RE: Windscreen Wipers On Aircraft
Username: Viscount724
Posted 2012-12-27 14:01:20 and read 6403 times.

Quoting rwessel (Reply 29):
On the SR-71, they used just a spray of rain-repellant fluid, without wipers. I'm guessing the flight environment was not conducive to the survival or rubber windshield wiper blades. IIRC, the XB-70 used a similar system.

The DC-8 also has no windshield wipers. It has a rain dispersion system using bleed air.

Topic: RE: Windscreen Wipers On Aircraft
Username: okie
Posted 2012-12-27 16:35:47 and read 6366 times.

Quoting yeelep (Reply 12):
On the 737's the answer is no and kinda. up to the NG's they have a fluid system like a cars. But instead of a washer type fluid, a product called Rainboe (think industrial strength Rainex) is sprayed. The NG's have none

There seems to be some confusion here.

First of all, "Rainboe" was not a washer fluid, it was a rain repellent as you indicated.
It came in aerosol cans and the valve and cans were prone to leaks, whether in use or not.

Rainboe was a Great Performer but a Bad Actor environmentally speaking. The solvents involved caused many problems for pilots when there were leaks in the valve area of the can in the confined space of the cockpit. As far as I know it was discontinued an if there is a suitable replacement then it still may be called Rainboe but I do not know that there is a replacement.

Washer fluids may or may not contain a repellent in its formula but is more along the lines of a washer fluid where the main ingredients are alcohol and water.

Okie

Topic: RE: Windscreen Wipers On Aircraft
Username: 2H4
Posted 2012-12-27 21:16:00 and read 6280 times.

I'm surprised wiper blades seem to be replaced so infrequently. The main reason I typically have had to replace the wipers on my cars over the years is UV degradation as opposed to wear from use. I would assume that because airliners spend their entire lives outside and much of their lives up at altitude, the rubber would wear fairly quickly due to UV exposure.

Topic: RE: Windscreen Wipers On Aircraft
Username: readytotaxi
Posted 2012-12-28 08:26:02 and read 6132 times.

Quoting 2H4 (Reply 34):
I would assume that because airliners spend their entire lives outside and much of their lives up at altitude, the rubber would wear fairly quickly due to UV exposure.

Yep that was what I was thinking when I made the post, and at high freezing altitudes I would have thought that would have made the rubber perish quicker.

Topic: RE: Windscreen Wipers On Aircraft
Username: JD747
Posted 2012-12-28 14:54:56 and read 6072 times.

Quoting barney captain (Reply 22):

The classic 737 wipers are so loud, I often joked that when they were needed, you could either see or hear - not both. Thankfully the NG 's are vastly improved and work beautifully

The A320 wipers are also very loud. I try not to use them, as much as I can, most of the times only during taxi, and some times on very sort final. Also, it only have two settings, slow and fast, so you have to switch it on and off continuously. Very annoying.

Regards

Topic: RE: Windscreen Wipers On Aircraft
Username: strfyr51
Posted 2012-12-28 16:18:39 and read 6031 times.

Quoting b78710 (Reply 1):

You are truly lucky, We change them about once a year per airplane at United. We change the arms when the springs break or they've lost tension.

Topic: RE: Windscreen Wipers On Aircraft
Username: Viscount724
Posted 2012-12-28 20:41:25 and read 5963 times.

Quoting barney captain (Reply 22):
The classic 737 wipers are so loud, I often joked that when they were needed, you could either see or hear - not both. Thankfully the NG 's are vastly improved and work beautifully.

Very brief segment of 737-200 wipers in operation between the 6:03 and 6:15 marks in this video of memorabilia on former Canadian regional carrier Nordair which was acquired by CP Air in the mid-1980s and then became part of Canadian Airlines. Nordair was based in YUL and mainly served the eastern part of the Canadian Arctic region, and charters to Florida, Caribbean etc.
http://www.youtube.com/watch_popup?v...wU4Nje9NjxT4ZwZmRI-Yw&feature=plcp

Topic: RE: Windscreen Wipers On Aircraft
Username: yeelep
Posted 2012-12-29 05:44:42 and read 5872 times.

Quoting okie (Reply 33):
Rainboe was a Great Performer but a Bad Actor environmentally speaking. The solvents involved caused many problems for pilots when there were leaks in the valve area of the can in the confined space of the cockpit. As far as I know it was discontinued an if there is a suitable replacement then it still may be called Rainboe but I do not know that there is a replacement.


We still use Rainboe Type 3. The MSDS was issued in 1992 with the last update in 2001, so its been around in its current state for a while. From what I read, its probably the same as or similar to the nasty stuff your'e taking about. Have never had a write up involving the can or valve leaking, knock on wood.

Topic: RE: Windscreen Wipers On Aircraft
Username: okie
Posted 2012-12-29 13:44:59 and read 5806 times.

Quoting yeelep (Reply 39):
We still use Rainboe Type 3.

Type 3 might be a clue.

I suspect the issue was with CFC-113 (Freon 113) CAS (76-13-1) which was the solvent for the repellent mixture along with providing the propellant. CFC-113 was seriously phased out by the EPA, it was also used for providing the expansion for foam insulation. Think fuel tank insulation issues with the Space Shuttle when 113 was phased out.

Again I do not know, you might check your MSDS.

Okie

Topic: RE: Windscreen Wipers On Aircraft
Username: yeelep
Posted 2013-01-05 12:52:33 and read 5223 times.

MSDS states Freon 113 90% by weight. The cans I looked at had Jan. 2007 dates.


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